1. Field of the Invention
The subject invention generally pertains to signal wiring used in monitoring a three-phase electrical power system. The invention more specifically applies to a method for determining whether the signal wiring is properly connected to the power system.
2. Description of Related Art
There are many available systems for determining whether a three-phase electrical power supply is properly connected to its load. The invention, however, actually pertains to the proper wiring of signal wires, not the proper wiring of the power lines.
Once a three-phase power supply is properly wired to its load, a control circuit can monitor the line voltage and current of all three phases to determine the system's power consumption and power factor. Six pairs of signal wires (three for the voltage readings and three for the current) can be used to couple the control circuit to the power lines. It is important for the signal wires to be properly wired. Otherwise, if one or more signal wires are inverted, the control will likely calculate incorrect values for the power consumption and power factor. In some cases, the control might even shut the system down unnecessarily.
When such problems occur, identifying the source of the problem or even recognizing the problem exists can be difficult and can result in costly service calls. Moreover, once the signal wiring is identified as causing the problem, it can be difficult to determine exactly which signal wires are wired incorrectly.
Consequently, there is a need for a system that can determine whether signal wiring used in monitoring a three-phase power system is properly wired; wherein the system preferably identifies any inverted pairs of wires that may exist.